Die-casting alloy compositions

ABSTRACT

A low liquidus temperature, ductile alloy containing 2-20 percent arsenic, and either manganese (15-45 percent), zinc (1550 percent) or a combination (15-55 percent) thereof, the balance being 40-65 percent copper, highly suitable for die casting.

States aiem Inventor George S. Foerster Midland, Mich.

Appl. No. 38,518

Filed May 18, 1970 Patented Jan. 11, 1972 Assignee The Dow Chemical Company Midland, Mich.

Continuation-impart of application Ser. No. 664,244, Aug. 30, 1967, now abandoned. This application May 18, 1970, Ser. No. 38,518

DIE-CASTING ALLOY COMPOSITIONS 6 Claims, No Drawings US. Cl 75/153, 75/134, 75/157.5, 75/161, 75/178,148/32 [51] Int. Cl [50] Field of Search...

[56] References Cited UNITED STATES PATENTS 2,338,756 1/1944 Crampton et al. 75/161 Primary Examiner-Charles N. Lovell Attorneys-Griswold and Burdick, Stephen S. Grace and William R. Norris DlE-CASTING ALLOY COMPOSITIONS This application is a continuation-in-part of Ser. No. 664,244 filed Aug. 30, 1967, now abandoned.

high concentration of arsenic in the alloy will be used. When manganese is employed with zinc, however, lower amounts of arsenic may be present in the alloy. For example, when the alloy contains from about 30 to 40 percent of manganese or BACKGROUND OF THE INVENTION from about 30 to 45 percent zinc, from about 8 to percent I c mi l copper b casting alloys generally have a of arsenic is used, whereas when the alloy contains from about liquidus temperature above about l,600 F. They are, there- 9 to 25 Percent manganese and frofn about 15 to 25 Percent fore, difficult to die-cast in that they cause considerable wear from l 5 to 7 P arsemc maxim E on h i o the other hand known copper base alloys In preparing the alloys of the present invention, convenwhich melt at lower temperatures are toobn'ttle for practical l0 P alloymg and meltmg teehmques as F x those u e In lc casting. For example, the copper base alloy cont i skilled in the art, may be employed. The alloying .COHSKIIUOI'RS mg 9.7 weight percent of magnesium melts at 1,332 F. 722 may comall} those amounts and yp of Impurities normally f while the cofper 2 225, g ir f 'l' lti fillz aing examples are representative of the novel 0 antimon metsat o aos, owever, are [with y copper base die casting alloys of the present invention but are Crampton (U.S. Pat. No. 2,338,756) di l a ductile not intended to be construed as limiting the invention thereto. copper-base alloy containing 0.1 to 5.0 percent As, 0.5 t vallous PP [1356 ll y were p eparedin ac ordance percent M n and up to 30 percent the copper content being withthe present invention by melting the constituents nan matlleastl6'i1 gtirfent.d However, alloys within these ranges have 20 gigg i o ggza a g a 2?}; 3 g; ggsg zggg'g'gfi re atlve y 1 iqut us temperatures.

A fi i f, i i-" -g is y? EJFZFLEZZLIZEE.'wilLi ial fiififii 8117331221 123 2211 co r ase o avm a ow 1 or us tern erat re an ing T y g q p u uc 40% Zn). The resulting melt in each case was cast into a 25 inch-diameter cylinder in a graphite mold. A l-inch-long sam- THE INVENTION ple was prepared from each cylinder and was tested for com- Th l pressive yield strength (CYS), ultimate compressive strength e R i f l comlmses 3 nova copper base alloy (CS), and percent compression C) which is a valid indicacolpposmon conslsuljg essemlany of from about 2 to about 20 tion of the ductility and therefore the utility of the alloys weight percent.ar.senlc and at least one P Selected 9 prepared. In addition, the liquidus temperature in degrees the group consisting of and the balanFe P Fahrenheit was ascertained for each alloy prepared. The parabout 40 to about weight copper when Sald Zmc ticular composition of each alloy made, its melting characused alone, the zinc composition ranges from about 15 to teristics, C CYS and CS, are presented in the following about 50 percent. When said manganese is used alone, the ble manganese comppslllon ranges from about 15 to about 45 Comparative alloys, not illustrative of the present invention, when i zmc and manganese are used together the were also prepared to show the high melting point properties g g of zmc and manganese ranges from about ,5 to of conventional copper base alloys as compared to the melting a Cu percent points of the present inventive alloys.

TABLE Nominal composition,

percent Llquidus In 1000's p.s.i. twig Mn Zn plus As PercentC CYS CS n p l i stlvefirt 3 3 1, 900 Ductile Comparative-R 6. 6 0 1. 0 1, 840 Ductile 1Comparative-C 1. 2 30 1. g 1, Egg zgmctiltg4 130 21:: III: a 1:520 29 60 10s 25. 5 6 1, 480 26 35 121 45. 1 9. 75 1, 350 N at tested 36 4 1, 560 40 39 124 19 5 1, 500 35 106 22. 1 6. 5 1, 480 48 49 163 16.6 6. 5 1, 470 12 27 44 19. 4 6. 5 1, 480 14 22 36 18. 8 6 1, 480 19 22 4s 45 12 1, 380 23 50 119 26. 1 7 l, 650 28 32 117 3o 10 1, 480 32 32 135 40 10 ,420 24 54 124 43 13 1, 480 12 45 100 1 Balance being copper.

Preferably the alloy of the present invention will contain from about 5 to about l5 percent arsenic, from about 15 to about 30 percent of manganese, or from about 15 to about 45 weight percent of zinc, or a combination of manganese and zinc from about 25 to about 45 weight percent.

Particularly advantageous alloys in accordance with the present invention contain from about 20 to about 30 weight percent manganese, from about 4 to about 8 weight percent arsenic, from about 15 to about 25 weight percent of zinc.

Although the present invention is characterized as a copper base alloy, it is recognized that in some cases due to the ranges of alloy substitutents copper may not be present in a predominant amount.

While the alloy composition of the present invention may be formulated to obtain the desired combination of a particular low melting point and ductility, generally when high concentrations of manganese or zinc are employed, a moderate to It can be readily seen from the data in the table that the present alloys (example l-l5) are ductile and are characterized by significantly lower liquidus temperatures than the comparative alloys (examples A-C), thus very suitable for use in die casting operations.

The present invention may be modified or changed without departing from the spirit or scope thereof and it is understood that the invention is only limited as defined in the appended claims.

What is claimed is:

l. A low melting, ductile alloy consisting essentially by weight of from about 2 to about 20 percent arsenic, and at least one metal selected from the group consisting of zinc and manganese, the amount of said zinc when used alone being within a range of from about 15 to about 50 percent, the amount of said manganese when used alone being within a range of from about 15 to about 45 percent, the total amount of said zinc and manganese when used together being within a range of from about 15 to about 55 percent, the balance being copper in an amount from about 40 to 65 percent.

2. The alloy of claim 1 wherein the metal present is manganese in an amount of from about 15 to about 30 percent, and the arsenic is present in an amount from about 5 to about percent.

3. The alloy of claim 1 wherein the arsenic is present therein in an amount of from about 5 to about 15 percent, and the metal selected is zinc in an amount of from about 15 to about 45 percent.

4. The alloy of claim 1 wherein the arsenic is present therein in an amount of from about 5 to about 15 percent, and the metals selected are zinc and manganese in a total amount of from about 25 to about 45 percent.

5. The alloy of claim 1 wherein the manganese is present therein in an amount of from about 20 to about 30 percent, the zinc in an amount of from about l5 to about 25 percent, and arsenic in an amount from about 4 to about 8 percent.

6. The alloy of claim 1 further characterized as having a liquidus temperature below about l,600 F.

t I I 

2. The alloy of claim 1 wherein the metal present is manganese in an amount of from about 15 to about 30 percent, and the arsenic is present in an amount from about 5 to about 15 percent.
 3. The alloy of claim 1 wherein the arsenic is present therein in an amount of from about 5 to about 15 percent, and the metal selected is zinc in an amount of from about 15 to about 45 percent.
 4. The alloy of claim 1 wherein the arsenic is present therein in an amount of from about 5 to about 15 percent, and the metals selected are zinc and manganese in a total amount of from about 25 to about 45 percent.
 5. The alloy of claim 1 wherein the manganese is present therein in an amount of from about 20 to about 30 percent, the zinc in an amount of from about 15 to about 25 percent, and arsenic in an amount from about 4 to about 8 percent.
 6. The alloy of claim 1 further characterized as having a liquidus temperature below about 1,600* F. 